U.S. Pat. No. 4,702,742 Iwata et al (1987), discloses a mixture to keep the ink from drying in a jet ink printing machine. The cloth to be imprinted requires pre-treatment with an acceptor before applying the ink. The mixture disclosed contains some substantial differences to the present invention in components and methods of preparation. For example, the compound is subjected to extensive mixing. The PH balance is adjusted by adding sodium hydroxide. In several examples the mixture was heated, changing the molecular structure of the compound.
U.S. Pat. No. 4,455,168 Togata et al (1984) discloses an ink mixture which is heated, changing the molecular structure of the mixture.
U.S. Pat. No. 5,419,8243, Tanaka (1978) discloses a mixture to mark occlusion in dentistry. The mixture used and the application are substantially different from the present invention.
The present invention is distinguished from all examples of the prior art because it combines a unique combination of ingredients without heating, to provide a mixture which will permanently imprint cloth without the necessity of pre-treatment acceptors in the cloth and will remain permanent in the cloth without heat setting and will remain wet and in conveyable form in the substrate over an extended period of time and yet dry quickly in a porous material to which it is applied. The invention also describes a procedure to impregnate a substrate which will contain the ink mixture in a conveyable form over an extended period of time.
Permanent imprinting of cloth conventionally requires that the cloth be pre-treated by an acceptor such as water soluble or hydrophilic natural or synthetic polymers, to enable the dye or ink or pigments to adhere to the cloth and be permanently imprinted and be able to withstand washing without the dye, pigments or ink being removed from the cloth. Additionally, permanent imprinting of cloth usually requires that the fabric be heat treated after imprinting for the purpose of setting the dye, ink or pigments in the fabric permanently.
Ink pads are known in which the ink does not dry out immediately in the ink pad, but the ink in these ink pads will wash out of cloth.
Permanent ink is known which, when poured on a stamp pad, can be used to imprint fabric and other porous surface and remains permanent on these surfaces. However, such ink dries quickly on the ink pad and additional ink must be supplied to replenish the ink pad.
At present there is no device, method, or chemical mixture for maintaining or containing permanent ink, dyes, pigments or the like in a conveyable form over an extended period of time to imprint textiles and other porous surfaces except for the above described liquid ink contained in bottles with its attendant disadvantages, or inks, dyes, pigments or the like which require treatment acceptors and heat setting which is costly and cumbersome.
In contrast this invention provides a product in which permanent ink, dyes, pigments or the like remain in a wet and conveyable in the substrate over an extended period of time. There is a need for this invention anywhere that clothing and personal items require identification. Such places include but are not limited to children's camps, the military, hospitals, prisons, nursing homes, little league baseball, school uniforms and like institutions.
For purposes of the present invention, permanently imprinted refers to the ability of the cloth to withstand 12 washings of detergents commonly used in households and the imprint of letters or numbers remains readable after the 12th washing.